Asterisk dialplan patterns

X matches any digit from 0-9
Z matches any digit form 1-9
N matches any digit from 2-9
[1237-9] matches any digit or letter in the brackets
(in this example, 1,2,3,7,8,9)
. wildcard, matches one or more characters
! wildcard, matches zero or more characters immediately
(only Asterisk 1.2 and later, see note)

References:
voip-info.org